It really is. Though some of it may be tissue lining from within your uterus as well, most of it is in fact blood. If you are curious, you really ought to check out the “Amazing Science Behind Periods” article. It’s a quick and easy-to-understand run-down of exactly what happens during your period. The more you understand the less squeamish you’ll feel about it!
Yes, menstrual blood is real blood, but I can understand why you ask. Sometimes it just doesn’t look like the blood when you have a cut. That’s because in addition to losing 4 to 12 teaspoons of blood per cycle, you’re also shedding the lining of your uterus. Doesn’t much make for a pretty sight, but it’s totally natural.
Yes, it is REALLY blood! During the second half of your cycle, the lining of your uterus (endometrium) begins to thicken in preparation for a fertilized egg. By then end of the cycle, if this does not happen, the hormones progesterone and estrogen begin to fall and that thickened endometrium begins to slough off. What you see in your menstrual flow are the cells from the uterine lining and blood from special arteries in the uterus.
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